textproduct: Rapid City

KEY MESSAGES

- A few light rain and snow showers will move across the area Thursday morning with little to no accumulation expected.

- More active weather returns for the weekend with the potential for showers, isolated thunderstorms, and temperatures surging into the 80s for many areas.

- Gusty winds, low relative humidities, and the chance for an isolated thunderstorm may also support elevated to near- critical fire weather conditions this weekend.

UPDATE

Issued at 1058 PM MDT Wed Apr 8 2026

Strong northwest winds across portions of our plains rapidly decreased as forecast this evening, and the WIND ADVISORY was allowed to expire as scheduled at 6 PM. Made a few minor tweaks to PoPs overnight tonight into Thursday morning as a very weak shortwave disturbance crosses the region supporting a few light rain/snow showers and a band of clouds, but QPF amounts are still expected to be near zero with many areas staying dry. The best chance for showers remains across the South Dakota plains east of Rapid City. Skies clear into Thursday afternoon. Finally...looking ahead to Saturday...noted that the current deterministic NBM high temperature forecast currently falls below even the 25th NBM percentile, with the 25th-75th percentile distribution tightly clustered. This could be a case where the blend is shy/struggling to fully "catch up" with and capture the sudden warmup compared to recent temperatures. There is certainly the potential that our high temperature forecast may need to be increased in future forecast updates, potentially extending into Sunday as well. As previously mentioned, both days will need to be watched for a combination of gusty winds, low relative humidities, and perhaps even an isolated thunderstorm or two to produce near-critical fire weather conditions over some decent real estate/coverage in our forecast area.

DISCUSSION

(This Evening Through Wednesday) Issued at 108 PM MDT Wed Apr 8 2026

Well defined upper low is currently moving across northern ND. Secondary cold front is pushing through the Northern Plains with core of 30-50kt winds at H850-H700 moving across northwestern SD. Sfc stations are reporting gusts of 45-55mph across northwestern SD with isolated gusts of 60+ mph. These winds should continue through the afternoon with widespread advsy (45+ mph) gusts with gusts of 60+ mph in some spots. Winds will diminish in the next few hours as the upper low pushes off to the east.

Second, much weaker shortwave will move through the region tonight/early tomorrow morning. Forcing and moisture should be enough to support some light snow showers (transitioning to rain across the western SD plains as temps warm up through the morning) across western SD. In terms of precip, NBM paints 50-70% probs for measurable precip (>0.01") across north central SD with HREF probs near zero.

Deterministic models in good consensus of shortwave ridging builds into the region Friday into Saturday as longwave trof progged to move into the western US. Lead shortwave ejects over the Central Plains Saturday afternoon with sfc cyclone developing in the lee of the Rockies. Southerly flow and WAA will support development of sfc thermal ridge into the Northern Plains with NBM probs showing 70-90+% of temps >75F Saturday afternoon. The very warm temperatures, breezy southerly flow, and low RHs will support elevated fire wx concerns Saturday afternoon. Forecast soundings Saturday afternoon also depict steep lapse low to mid-level lapse rates and weak buoyancy (500-1000 J/kg CAPE), supporting the potential for showers and perhaps a few thunderstorms though limited moisture may preclude widespread convection. Upper trof moves into the western US by early next week, bringing more substantial chances for wetting precip for Monday.

AVIATION

(For the 06Z TAFS Through 06Z Thursday Night) Issued At 1058 PM MDT Wed Apr 8 2026

Gusty northwest winds rapidly decreased earlier this evening as forecast, generally ending aviation impacts for the TAF period. A very weak shortwave disturbance will cross the region tonight supporting a few light rain/snow showers and a band of clouds, but a review of the CAMs suggests very, VERY low chances of precip near KGCC and KRAP with the best chances across the South Dakota plains north and east of KRAP. For now, will continue with a dry aviation forecast and keep clouds in the mid-levels, well above VFR thresholds. Only a slight diurnal increase in winds is expected Thursday afternoon with clearing skies, with those winds trending down again around sunset. Next chance of precipitation and even an isolated thunderstorm arrives this weekend.

UNR WATCHES/WARNINGS/ADVISORIES

SD...None. WY...None.